diff --git a/bin/pulsar-daemon b/bin/pulsar-daemon
index 9848c26d33158..154233f36efa4 100755
--- a/bin/pulsar-daemon
+++ b/bin/pulsar-daemon
@@ -151,6 +151,7 @@ case $startStop in
 
     rotate_out_log $out
     echo starting $command, logging to $logfile
+    echo Note: Set immediateFlush to true in conf/log4j2.yaml will guarantee the logging event is flushing to disk immediately. The default behavior is switched off due to performance considerations.
     pulsar=$PULSAR_HOME/bin/pulsar
     nohup $pulsar $command "$@" > "$out" 2>&1 < /dev/null &
     echo $! > $pid